Window OS Validation

I want to know Window OS Validation(Window 7 , Window XP) in javascript.
I want to resize window page size.
Please help me.

This is my code

function OpenWindow(url, targetName, width, height) {
     var features = 'location=no,menubar=no,toolbar=no,status=yes,resizable=yes,scrollbars=no,directories=yes';
     var openWin = window.open(url, targetName, features);
     if (openWin == null) {
         return openWin;
     }
     openWin.moveTo(0, 0);
     **openWin.resizeTo(1020, 738);**
     openWin.focus();
     return openWin;
 
 }
 

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